Omron CJ1W-MA - REV 10-2008, Operation Manual

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Using Direct Operation Section 9-4
9-4-3 Changing Target Position
during direct operation, the target position for the positioning operation can be
changed by setting a new position command value in the Axis Operating Out-
put Memory Area and executing ABSOLUTE MOVEMENT or RELATIVE
MOVEMENT again.
The Busy Flag remains ON during direct operation until the positioning opera-
tion is completed. The Receiving Command Flag in the Axis Operating Input
Memory Area is used to control the ON/OFF timing of the ABSOLUTE/RELA-
TIVE MOVEMENT Bit to change the target position. The target position can
be changed when the Receiving Command Flag is OFF. When executing the
target position change, make sure that the ABSOLUTE/RELATIVE MOVE-
MENT Bit remains ON until the Receiving Command Flag turns ON.
Note (1) When executing movement commands sequentially, make sure that the
movement command bit remains OFF for a minimum of either the PLC
cycle time
×
2 or the MECHATROLINK communications cycle
×
2, which-
ever is longer. If the time when the movement command bit is OFF is too
short, the PCU will not be able to detect the rising edge of the movement
command bit, preventing reception of the command.
(2) When executing the movement command again during axis operation to
change the target position, do not change the acceleration/deceleration
curve designation from the original setting when operation was started.
Changing the acceleration/deceleration curve designation when chang-
ing the target position during axis operation may result in displaced posi-
tioning or other malfunction.
2710 hex (10000)
3E8 hex (1000)
2EE0 hex (12000)
Position command value
(words a+2, a+3)
Speed command value
(words a+4, a+5)
RELATIVE MOVEMENT
(word a, bit 04)
Receiving Command
Flag (word b, bit 00)
Busy Flag (word b, bit 13)
Speed
PCU Positioning Completed
Flag (word b, bit 05)
Target speed: 1,000
(command units/s)
Previous target position
(absolute position: 10,000)
Target position changed
a = Beginning word of Axis Operating Output Areas specified in Common Para (Axis No.
−
1)
×
25
b = Beginning word of Axis Operating Input Areas specified in Common Para (Axis No.
−
1)
×
25
The Receiving Command Flag turns ON for at least
one cycle time when a command is received to start
direct operation or change the target position. During
direct operation, the Busy Flag remains ON until
positioning is completed. Therefore, control the
movement command timing for changing target
positions using the Receiving Command Flag.
Solid line: Command speed
Broken line: Feedback speed
Time
Final position: 12,000 (command units)